Phenomenal gems seem to do magical things with light. Learn the science behind optical effects like cat’s eyes and star stones and how to judge their value.
18 Minute Read
In most cases, a phenomenal effect will add beauty as well as value to a gem. However, when evaluating phenomenal gems, gemologists must consider many factors. Exceptions can arise.
A gem’s relative rarity and popularity will often adjust the impact any phenomenal effect will have on its value.
For example, mother of pearl is a phenomenal gem that’s so common it’s not valuable. On the other hand, some stones are so rare there’s just little demand for them. Although very rare, tenebrescent hackmanite isn’t worth nearly as much as a more common, more popular star sapphire.
Most of the grading criteria for phenomenal gems are the same as for other stones: color, clarity, carat and, to a lesser degree, cut. For example, star…
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In most cases, a phenomenal effect will add beauty as well as value to a gem. However, when evaluating phenomenal gems, gemologists must consider many factors. Exceptions can arise.
A gem’s relative rarity and popularity will often adjust the impact any phenomenal effect will have on its value.
For example, mother of pearl is a phenomenal gem that’s so common it’s not valuable. On the other hand, some stones are so rare there’s just little demand for them. Although very rare, tenebrescent hackmanite isn’t worth nearly as much as a more common, more popular .
Most of the grading criteria for phenomenal gems are the same as for other stones: color, clarity, carat and, to a lesser degree, cut. For example, star…
Phenomenal gems seem to do magical things with light. Learn the science behind optical effects like cat’s eyes and star stones and how to judge their value.
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